Lapping-machine tool



Oct. 30, 1923. 1,472,422

w. J. ALLESET AL LAPPING MACHINE TOOL Filed July 12 1921 E 4%. .KEEIQENEH. n I" I I *woamto'ca, l V/u/AM, 6. gulf-s.

. f1 BERT. mw auwi fifi? 0 Patented Oct. 30, 1923.

UNITED STATES PATENT OFFICE.

WILLIAM J. ALLES AND SIDNEY C. PROBERT, F DETRCI'I, MICHIGAN, ASSIGNOBS T0 DODGE BROTHERS, 0F DETROIT, MICHIGAN, A CORPORATION OF MICHIGAN.

LAPPING-MACHINE TOOL.

Original application flied .Inly 15, 1920. Divided and. this application-filed July 12, 1821. Serial No.

To all whom it may concern:

Be it known that we, WILLIAM J. Anna and SIDNEY C. PRoBER'r, citizens of the United States, both residing at Detroit, Michigan, have invented certain new and useful Improvements in Lapping-Machine Tools,

of which the following is a clear, full, and exact description.

Our invention relates to lapping machines and particularly to the construction of an improved tool to be used in machines of this character, and more speciall in the machine shown in our application I filed July 15, 1920 for cylinder lapping machines of which the present application is a division. p I

An important feature of the lapping tool consists of the provision of a plurality of I abrasive stones, said stones being mounted 29 in the tool in such a manner that pressure exerted thereby on the walls of the cylinder,

or other surface to be lapped, is substantial-- ly constant during the life of the stone.

. Another feature of the invention consists .of the revision of a single means arranged to yiel ingly exert outward radial pressure against the stones forming the tool.-

. Other features and advantages will bei come apparent from the following detailed 30- description and claims when taken in connection with the accompanying drawings, in which Fig. 1 is a view of the frame which supports one of the lapping stones; 85 Fig. 2 isa longitudinal sectional view of the lappingtool, and

Fig. 3 is a cross sectional view of the same taken on the line 3-3 of Fig. 2.

Referring to the drawings, each lapping 40 tool consists of a frame 17 having a plurality'of recesses 18 shown in Fig. 3 arranged symmetrically about its circumference and also having a longitudinal central bore 19. Set into each of the recesses 18 is a support 4.8 or shoe 22 for a lapping stone 23. The inner wall. of each recess is slotted, as shown at 20, Fig. 1, and each shoe 22 has at each end thereof a lug 21 which proi'jects through the slot and into the central ore ofthe frame yieldingly press against t erial #396,582,

17. In order that the lapping stones 18 may e walls of the cylinder during the lapping operation,;we provide a spring 24 mounted on a spindle 25, each end of said spring carrying a ring 26 hav ng a cam surface 27 which engages the inner cam faces of the lugs 21, the spring at this time being under compression. From Fig. 2 it will be readily seen that the tendencyof the spring to ex and will exert a camming action against t e lugs 21, which in turn will cause radial outward pressure to be exerted against all of the stones 23. The stones are confined at the top and bottom of the tool by plates 28 and 29, plate 28 being screwed to the frame 17 by screws 30, while the plate 29 is secured to said frame by the screws 31. Said plate 29 is formed with a screw threaded socket 32, to which a shaft may be secured, said shaft furnishing the means whereby each lapping tool is rec1procated and rotated, as described in our application above referred to.

From the structure so far described, it

will be apparent that since the plates 28 and 29, together with the recesses 18, or at least that portion thereof can-yin the lapping stones, form a straight walle pocket or recess into which a stone fits, the tool would fall apart by reason of the spring pressure if means were not rovided to prevent it. In order to prevent-t is, when the tool is not engaged by the walls of the cylinder-to be lapped, we provide a retaining frame, such as described in our application of which this is a division.

In order to permit ready assemblage of the tool, it is. desirable that all pressure on the spring be temporarily relieved, and to accomplish this we provide a flattened head 33 on the'spindle' which is in engagement with the outside of the cam ring 26 shown in the upper part of Fig. 2.. Engaging the lower or outer part of the lower cam ring 26 is a thimble 34 loosely engaging the spindle 25. .An adjusting nut 35 is provided, and the s indle has a screw slot in its head. Turning of the nut one way or the other,

therefore, will result in varying the tension of the spring, and when turned to the right the spindle will act to clamp the spr1n between the two cam rings 26 so as to re leve all pressure of said cam rings against the lugs 21. With the pressure thus relieved, the stones may be assembled in the recesses of the frame and the tool inserted in the retaining frame, after which the adjusting nut may be unscrewed to permit the spring to exert its pressure against the stones.

For the purpose of readily adjustmg the spring tension, we provide a tool consistlng of a combined screwdriver and wrench. This tool is shown in Fig. 2,and consists of a-sleeve 36' having an enlarged head 37 for engagement with the nut 35. Through the sleeve passes a screwdriver 38 having at its end a handle 39 by which the screw may be held from turning while the nut is being adjusted. The sleeve 36 is also provided with a handle 40, and between the two handles is l interposed a spring 41 for normally holding the end of the screwdriver out of contact with the screw slot in the spindle 25. In operation, the tool is inserted and the handle 39 pressed to engage the screwdriver with the spindle to prevent turnin of the same.

The handle is then manipu ated to loosen the nut 35 until the spring 24 acquires the desired tension. The adjusting tool is re moved, and the lapping tool is then in condition to function.

Having thus described our invention,

. what we claim and desire to secure by Letters Patent is:

1. In a lapping tool, the combination with a plurality of lapping stoneseach mounted for movement radially as a unit, of a spring situated within said tool, and connecting means between said spring and both ends of each stone whereby uniform radial pressure is exerted by said spring against-said stones.

r 2. A lapping tool having a coiled spring extending longitudinally therein, a pluralit of lapping stones carried by said tool eac 1 stone mounted for independent radial movement, cam lugs associated with each of said stones one lug near each end thereof, and

means carried by said spring for engagement with said cam lugs. '3. A lapping tool havin a coiled s ring extending longitudinally t erein, a pliirality of lapping stones carried by sald tool each stone mounted for independent radial movement, cam lugs associated'with each of said stones one lug neareach end thereof. and a cam ring at each end of the spring for engagement with the cam lugs adjacent thereto. 7 v

4. A lapping tool having a coiled spring extending longitudinally therein, a plurality of lapping stones carried by said tool, cam

.lugs associated with each of said stones one lug near each end therof, and a cam ring at each end ofthe spring for engagpment with each end thereof, means carried by said 7 spring for engagement with the cam lugs adjacent thereto when such spri is compressed, and means carried by sai spindle for compressing said spring.

6. A lapping tool comprising a frame having a coiled spring extending longitudinally therein, a spindle supporting said spring, a plurality'of lapping stones, cam ugs associated with each stone one lug near each end thereof, a cam ring at each end of said spring, each ring having an outwardly facing surface for engagement with the lugs adjacent the ring when said spring is compressed, and means carried by the spindle for engagement with said cam rings to compress said spring therebetween.

7. A lapping tool comprising a frame lugs adjacent each ring when said spring is compressed, said spindle having one end screw threaded, means carried by the other end of said spindle for hearing against one cam ring, and means at the threaded portion 7 for bearing against the otheriring to thereby compress the spring between the two rings.

8. A lapping tool comprising a frame having a coiled spring extending longitudinally therein, a spindle supporting said spring, a plurality of lapping stones, cam lugs associated with each stone one lug near each end thereof, and means carried by said spindle whereby the power of said spring is exerted through said cam lugs to cause outward radial pressure against said stones.

9. A lapping tool comprising a frame having a coiled spring extending longitudinally therein, a spindle supporting said spring, a, plurality of lapping stones, cam lugs associated with'each stone one lug near each end thereof, a cam ring at eachend-of 53m cam ring, a. thimble bearing against the Signed at Defiroit, Michigan, this 6th dizzy olrier side of the other cam'ring and loosely of July, 1921.

engaging said spindle and nut screw WILLIAM J. ALLES threaded to said spindle and bearing against- SIDNEY C. PRQBERTV 5.52116. k-himnle whereby said spring may be Witnesses:

compressed between six id cam rings on ad- ALFRED H. KNIGHT,

gusinwn'i sai nut, BEN P. MOORE. 

